Sed command get version number from spec file and increment last
number by one. Work like old awk command was intended to work.

Source: https://stackoverflow.com/questions/14348432/how-to-find-replace-and-increment-a-matched-number-with-sed-awk/14348899

  This will allow services to install drop-in files into these folders
  for the 'readonly-root' service, but that service won't have to be
  installed by default as a result...

  Resolves: RHBZ#1585321

  This concept is quite outdated, and not sane to use at all.

  Use 'git log' instead...

  This installs the real scripts into /etc/sysconfig/network-scripts
  while leaving the management of the launchers in /usr/sbin to the
  alternatives system.

  This allows coexistence with alternative implementations of ifup
  and ifdown, notably NetworkManager.

  A priority of 90 is chosen rather arbitrarily, NetworkManager will
  use a lower one (50) so that our implementation takes precedence over
  NetworkManaager in case both are installed. In an unlikely event the
  user will want to switch to NetworkManager implementations when both
  are installed they can override the default with:

  $ update-alternatives --config ifup

  'check' and 'syntax-check' rules were dropped, as they seem obsolete
  nowadays (we are not using them at all)...

  The symlinks are no longer needed. Enablement of default services is
  now managed by 'fedora-release' package.